Power driven block and tackle

ABSTRACT

A portable power driven single sheave block and tackle with a motor means secured to one side of the block for rotating the sheave when the motor is energized. The sheave is provided with a plurality of peripheral jaws adapted to be automatically moved to engage a rope within a predetermined range of diameters and including means for securing the block to a support for angular movement for dispensing and retrieving the rope within a wide range of horizontal and vertical directions.

United States Patent 1191 Niskin Sept. 17, 1974 [54] POWER DRIVEN BLOCK AND TACKLE 3,287,987 11/1966 Getz et a1. 74/230.17 3,635,441 1/1972 H 254/138 [76] Inventor: shale Lucaya 3,643,921 2/1972 254/138 Mlaml, Fla. 33131 [22] Filed: Feb. 2, 1973 Primary ExaminerRichard A. Schacher I 2 I pp N 329 212 Assistant Examiner-Jeffrey V. Nase [57] ABSTRACT [52] US. Cl. 254/138, 43/8, 74/230.l7 M,

R A P01131316 power dI'IVell smgle sheave block and 51] 1111. C1 AOlk 73/06, F16h 55/56 tackle means Secured one We of the [58] Field of Search 254/135 R, 137, 138, 188, 254/l90 R, 191; 74/230.17 M, 230.24; 43/8, 6.5, 188/8284, 65.1, 67; 226/182 block for rotating the sheave when the motor is energized. The sheave is provided with a plurality of peripheral jaws adapted to be automatically moved to engage a rope within a predetermined range of diame- [561 Referemscie 235,21? J2133513131 1125333323213li'd a or 1 g a re- UNITED STATES PATENTS trieving the rope within a wide range of horizontal and 2,733,531 2/1956 Puretic 254/138 vertical direction, 2,752,797 7/1956 Sherwin... 74/230.24 2,852,952 9/1958 Wolfram 74/230.24 7 Claims, Drawing Figures 11 III mE-mmw 1 1 m SHEET 2 0F 4 FIG. 6

PAIENIEB SEN mu SHEEI 3 [IF 4 PAIENIEB scr I 1 Ian SHEET R [If 4 FIG. 17 1s POWER DRIVEN BLOCK AND TACKLE This invention relates in general to a protable power driven single sheave block and tackle for dispensing and retrieving a rope of a predetermined range of diameters in a linear path.

Prior to this invention, an ordinary portable single sheave block used for dispensing and retrieving a rope is supported at a strategic position with respect to a fixed position drum-type power winch, which greatly limits the position and placement of the block with respect to the drum of the power winch and limiting the range of the path of movement of the rope with respect to the block support.

The present invention overcomes the above limitations by eliminating the necessity, in many applications, of the use of one or more fixed winches and provides a simple means for positioning a suspending a block and tackle means for power controlling a rope in each of a wide range of strategic positions and directions.

A principal object of the invention is the provision of a block having a motor means secured thereto for rotating the sheave therein at a predetermined speed when the motor is energized with the sheave of the block having a plurality of jaw means around the periphery thereof for gripping and retrieving rope through the swallow of the block when the motor is energized.

Another object of the invention is the provision of a power driven sheave having a plurality of gripping jaws in parallel spaced facing relation around the periphery thereof with each of the jaws adapted to cam toward each other when frictionally constrained by the rope prior to gripping the rope therebetween.

A further object of the invention is the provision of a power driven sheave in a block having a plurality of camming jaws around the periphery of a power driven sheave with each of the mating sides of the jaws having a divergent surface for automatically engaging and retrieving a rope positioned therein with each within a predetermined range of diameters when said sheave is rotated.

Another object of the invention is the provision of a plurality of alternate type gripping jaws in the periphery of a power driven sheave with the divergent facing sides thereof adapted to grip a ripe therebetween for both power dispensing and retrieving a rope.

These and other objects and advantages in one embodiment of the invention are described and shown in the following specification and drawings, in which:

FIG. 1 illustrates a .water craft in reduced scale, with a power driven block and tackle supported by a boom with the rope thereof supporting a submerged load.

FIG. 2 is a side elevation of the power driven block in reduced scale.

FIG. 3 is a right hand end elevation of the block shown in FIG. 2.

FIG. 4 is an enlarged cross sectional left hand end view, taken through section line 44, FIG. 2.

FIG. 5 is an enlarged cross sectional side view taken through section line 55, FIG. 3, with a portion thereof broken away.

FIG. 6 is a perspective view of the left half portion of the sheave shown in FIG. 5.

FIG. 7 is a perspective view of one of the peripheral jaws positioned for independent movement in half portion of the sheave.

FIG. 8 is an inverted perspective view of the jaw shown in FIG. 7.

FIG. 9 is a cross sectional side elevation taken through section line 9-9, FIG. 4.

FIG. 10 illustrates a pair of adjacent one way jaws shown in FIG. 7 retained in non-gripping position.

FIG. 11 is the same as FIG. 10, except the jaws are in the rope gripping position.

FIG. 12 is a cross sectional view taken through section line l212, FIG. 5, showing the gripped rope illustrating in FIG. 11.

FIG. 13 illustrates a jaw having two one-way tapered cavities for gripping a rope for movement in one direction.

FIG. 14 and 15 illustrate the one way jaws positioned in the periphery of the sheaves and operated by the rollers shown.

FIG. 16 illustrates an alternate jaw having two tapered cavities therein for gripping the rope for movement in opposite directions.

FIG. 17 illustrates a pair of jaws retained in the sheave by ball bearings in a neutral non-gripping position.

FIG. 18 is a cross sectional radial view taken through section line 18-18, FIG. 17.

FIG. 19 illustrates the action of the jaws when moved to gripping position by the counterclockwise rotation of the sheave.

FIG. 20 illustrates the gripping positions of the jaws when the sheave is rotated in a clockwise direction.

FIG. 1 illustrates a water craft 1 and a power driven block and tackle assembly 2 suspended from a conventional boom 3 with a rope 4, sometimes called a line, supporting a load 5 at the outer end thereof. It is apparent that the power driven block and tackle assembly has a wide variety of uses other than the marine illustration in FIG. 1, more particularly for retrieving nets for the collection of marine life as well as for use in building construction, loading and unloading warehouse material, etc.

FIGS. 2, 3, and 4 show the principal elements in their working relation, such as two halves of the main frame 6L and 6R of the block, which are secured together at the lower end by a bolt and nut 7 and retained at the upper end by two plates 88 which are secured in facing relation to the outside surfaces of the frame 6L and 6R by screws 9-9 which terminate in the upper ends that form a clevis extension 10 which is spaced by a dual shoulder bushing 11 in compressed relation between the elements 10-10 by a bolt 12 and nut 13.

In this particular embodiment, a hook 14 is shown loosely engaged with bushing 11 for supporting the block from a dual swivel means 15 and a suspension member 16.

Referring to FIGS. 2, 3, and 4, a hydraulic motor 17 is secured to the right side 6R of the block by four screws 18 and the motor is energized through input and output flexible fluid conduits 19-19. The output drive shaft 20 of the motor is best shown in FIG. 4, which is journalled for rotation on flanged bushings 2l21 in the frame members 6L and 6R, respectively.

The sheave assembly consists of a pair of like members 22 with mating sides secured together in coaxial relation by four bolts 23 and nuts 24. The sheave is secured for rotation by shaft 20 between the inner sides of bushings 21 by a key 25. A right angled groove is provided in the outer periphery and inner side of each sheave member which forms a central rectangular groove 26 around the periphery of the assembled sheave when the two members are bolted together. A cylindrical band 27 is snugly fitted around the shoulder of the groove for alignment purposes, as illustrated in FIGS. 4 and 9.

Each frame member 6L and 6R has like divergent peripheral sloping sides 28s forming a V with an open apex of predetermined inner width with a central opening 29 for passing the maximum diameter rope to enter the rectangular groove 26 in the sheave assembly.

It is to be noted that the circular sloping sides 28S encompass the periphery of the frame member 6L and 6R except for a portion at the lower end thereof which is occupied by the lower junction of the frame members 6L and 6R.

FIG. 6 illustrates the inner wall of each of the two sheave members 22 which form the peripheral groove in which there are ten adjacent spaced segment cavities in each side of the aforesaid groove 26, shown in FIG. 4. Each of said cavities has a circular planar slope at a predetermined angle forming ten like vertical angular surfaces in equi-spaced relation extending in like direction around the surface of each side of groove 26.

FIGS. 7 and 8 show a single arcuate jaw 31 having a circular cavity 32 of predetermined constant depth with the bottom planar surface in one side thereof and a radially divergent angular surface at a predetermined angle on the opposite outer side thereof.

Referring to FIGS. 1, 5, and 6 each half groove 26 in each half of the sheave 22 is provided with 10 radial cavities with a bottom surface at a predetermined angle forming a planar cam surface 30 in which ten cylindrical rollers 34 of predetermined diameter are retained in predetermined end to end spaced relation for rotation along each angular cam surface 30 and the bottom surface of cavity 32 in each half of the sheave.

Referring to FIG. 9, the cross sectional view shows a rope 35 threaded through the passageway through the block, sometimes called a swallow, and engaged with four of the ten jaws 31 bearing against the angular surface 338 of each jaw.

FIG. 12 shows a pair of adjacent jaws 31 with their respective surfaces 338 bearing against opposite sides of the rope 35 resulting from the action of rollers 34 rolling upward on the incline surfaces 30 in each half sheave which secures the rope for continuous linear movement between the jaws when the sheave is rotated and the rope is constrained to permit the entry of the rope between the jaws for compression thereby.

FIG. 12 also illustrates that all of the jaws are captivated within the groove of the sheave for lateral movement since the wide portion of each jaw has movement only to the extent of the roller travel on the inclined surface 30. It is to be noted that the over hang of the two halves of the sheave must be parted to remove or install each jaw.

FIGS. 10 and 11 illustrate the movement of the jaw from normal open release position shown in FIG. 10 to a gripped position for retrieving a rope in one direction only. 7

FIG. 11 illustrates the clamping action of the jaws resulting from the pair of rollers rolling upward on their respective inclined surfaces for clamping the smallest diameter rope 35.

FIGS. I3, 14, and 15 illustrate an alternate construction whereby each jaw 31a is provided with two inclined cavities 30a for gripping the rope, and wherein the cavities in each side surface of the groove 26 are rectangular instead of angular, as shown, in FIG. 6, which dual cavities are operated by a pair of rollers which also prevents the jaw from the slight tilting experienced in the foregoing described single roller jaw. Pockets 300 have the same incline as shown in FIG. 6. It is apparent that pockets 32a having rollers 34 are the same, but are now parallel with sides of the groove in each of the half mating sheave members. This dual construction assures a greater and more uniform gripping force on the rope 35.

Another useful alternate construction shown in FIGS. 16, 17, and 18 provides for a jaw 31b in which a pocket in one side forms a pair of divergent inclines 3636, shown in FIG. 16, and hemispherical sockets in each sidewall of the groove in the sheave for retaining two pairs of ball bearings 37 as an alternate to the rollers 34, which results in lower costs and greater security for gripping the rope and provides for power driving the rope and dispensing or retrieving same dependent upon the direction of rotation of the driving motor 17. The idle non-gripping position of the reversible gripping jaw is shown in FIG. 17.

FIG. 18 is a cross-sectional view taken through section line 18l8, FIG. 17, showing the central or open position of the jaws 31b within the groove of the sheave and the ball pockets in spaced relation in each side of the grooves of the sheave in relation with the frame members 6L and 6R.

In operation, a rope, having a diameter within the aforesaid predetermined range, is passed through the passageway of the block and moved by the sloping sides 28s thereof to enter the V opening of a plurality of jaws 31 with the number of engaged jaws being dependent upon the wrap of the rope on the sheave. It is then important to constrain the rope in reverse direction from the desired retrieving direction in order to move the jaws into their open gripping position for engaging the rope therebetween. Then the sheave is rotated in the desired direction for retrieving the line, which automatically grips same by the progressive movement of the jaws toward each other by the frictional contact with the jaws in opposite sides in the groove of the sheave.

It is obvious that the rope may be properly engaged in the jaws by either hand means or a slight reversal of the motor I7.

It is also obvious that an electric motor with an appropriate built-in speed reducer may readily be substituted for the hydraulic motor shown for such installations where electric power is available.

It is also to be noted that the dual direction gripping jaws will require a reversible type motor of either the hydraulic or electric type to retrieve a rope in opposite directions.

It is to be understood that certain modifications in construction are intended to come within the scope and teachings of the above specification.

Having described my invention, I claim:

1. A power operated block comprising means formmg a frame consisting of two sides secured together with a support coupling means extending from the upper end thereof and having a transverse passageway therethrough which includes a sheave clearance space.

a motor means secured to one outer side of said frame with the drive shaft thereof journalled in said frame substantially central and transverse said sheave space,

a sheave of predetermined diameter positioned in said space secured coaxial to said shaft for rotation thereby including a predetermined groove of uniform rectangular cross section in the outer periphery thereof forming two spaced surfaces on opposite sides of said groove normal the axis of said shaft and terminating in a coaxial cylindrical bottom surface.

each of the spaced surfaces of said sheave having a plurality of like equally spaced circular segmental cavities therein with said cavities tapering inward in a like direction a predetermined angle and a predetermined depth,

a plurality of spaced segmental jaws positioned in end to end relation against each said side of said groove for predetermined limited axial rotary movement therein about said bottom surface,

each of said jaws having a segmental circular cavity of predetermined depth in the side against each said side of said groove and the opposite side of each of said jaws having a predetermined tapered outer opposite side,

a cylindrical roller of predetermined dimension positioned within each said cavity in said groove surface and in the said circular cavity in each said jaw for moving each of said opposite jaws toward each other from said surface of each said sheave when said jaws are rotated by a rope positioned between said tapered outer side of said jaws and whereby a rope positioned through said passageway in said frame and engaging a portion of said convergent outer taper of a plurality of jaws will be constrained in one direction and move said jaws to their gripping position and said jaws rotated about a portion of said sheave when said motor means is energized to retract said rope.

2. The construction recited in claim 1 wherein said frame includes a circular V-shaped tapered entry for guiding a rope between said jaws and whereby the lower terminus of said V-shaped sides of said frame have a predetermined hang-over said jaws for retaining same in their working position.

3. The construction recited in claim 1 wherein said motor means comprises a hydraulic motor including flexible input and output conduits for connection in a pressurized hydraulic system.

4. The construction recited in claim 1 wherein said motor means comprises an electric motor including flexible conductors for connection to a source of electric energy.

5. The construction recited in claim 1 wherein the opposite sides of said surface of said groove will have a like plurality of arcuate cavities with a bottom surface parallel said groove surface and each of said jaws will have an angular cavity therein of predetermined angle and depth generally positioned in mating relation to each said cavity in said groove surface for retaining said rollers.

6. The construction recited in claim 1 wherein two pair of ball bearings are positioned in each of said cavities in said groove surfaces and in each of said cavities in each said jaw whereby the movement of said jaws in one direction will move the opposite jaws toward each other for gripping a rope.

7. The construction recited in claim 1 wherein each of said oppositely positioned jaws have a dual angular cavity with a central low junction and each of said surfaces of said groove have a spherical cavity for retaining a pair of ball bearings for contact with said dual angular recesses in said jaws whereby the movement of said jaws in each opposite direction will move the jaws toward a rope therebetween for gripping same. 

1. A power operated block comprising means forming a frame consisting of two sides secured together with a support coupling means extending from the upper end thereof and having a transverse passageway therethrough which includes a sheave clearance space, a motor means secured to one outer side of said frame with the drive shaft thereof journalled in said frame substantially central and transverse said sheave space, a sheave of predetermined diameter positioned in said space secured coaxial to said shaft for rotation thereby including a predetermined groove of uniform rectangular cross section in the outer periphery thereof forming two spaced surfaces on opposite sides of said groove normal the axis of said shaft and terminating in a coaxial cylindrical bottom surface. each of the spaced surfaces of said sheave having a plurality of like equally spaced circular segmental cavities therein with said cavities tapering inward in a like direction a predetermined angle and a predetermined depth, a plurality of spaced segmental jaws positioned in end to end relation against each said side of said groove for predetermined limited axial rotary movement therein about said bottom surface, each of said jaws having a segmental circular cavity of predetermined depth in the side against each said side of said groove and the opposite side of each of said jaws having a predetermined tapered outer opposite side, a cylindrical roller of predetermined dimension positioned within each said cavity in said groove surface and in the said circular cavity in each said jaw for moving each of said opposite jaws toward each other from said surface of each said sheave when said jaws are rotated by a rope positioned between said tapered outer side of said jaws and whereby a rope positioned through said passageway in said frame and engaging a portion of said convergent outer taper of a plurality of jaws will be constrained in one direction aNd move said jaws to their gripping position and said jaws rotated about a portion of said sheave when said motor means is energized to retract said rope.
 2. The construction recited in claim 1 wherein said frame includes a circular V-shaped tapered entry for guiding a rope between said jaws and whereby the lower terminus of said V-shaped sides of said frame have a predetermined hang-over said jaws for retaining same in their working position.
 3. The construction recited in claim 1 wherein said motor means comprises a hydraulic motor including flexible input and output conduits for connection in a pressurized hydraulic system.
 4. The construction recited in claim 1 wherein said motor means comprises an electric motor including flexible conductors for connection to a source of electric energy.
 5. The construction recited in claim 1 wherein the opposite sides of said surface of said groove will have a like plurality of arcuate cavities with a bottom surface parallel said groove surface and each of said jaws will have an angular cavity therein of predetermined angle and depth generally positioned in mating relation to each said cavity in said groove surface for retaining said rollers.
 6. The construction recited in claim 1 wherein two pair of ball bearings are positioned in each of said cavities in said groove surfaces and in each of said cavities in each said jaw whereby the movement of said jaws in one direction will move the opposite jaws toward each other for gripping a rope.
 7. The construction recited in claim 1 wherein each of said oppositely positioned jaws have a dual angular cavity with a central low junction and each of said surfaces of said groove have a spherical cavity for retaining a pair of ball bearings for contact with said dual angular recesses in said jaws whereby the movement of said jaws in each opposite direction will move the jaws toward a rope therebetween for gripping same. 